1. Field of the Invention
This invention relates to novel multibinding compounds (agents) that inhibit microsomal triglyceride transferase protein (MTP) and to pharmaceutical compositions comprising such compounds. Accordingly, the multibinding compounds and pharmaceutical compositions of this invention are useful in preventing and treating various disorders associated with hyperlipidemia and related disorders, such as atherosclerosis.
References
The following publications are cited in this application as superscript numbers:
.sup.1 J. R. Wetterau et al., Biochim. Biophys. Acta 1997, 1345, 136-150. PA1 .sup.2 D. A. Gordon et al., Trends Cell Biol. 1995, 5, 317-321. PA1 .sup.3 Robbins Pathological Basis of Disease, 5.sup.th Edition (1994), pp. 473-484. PA1 .sup.4 S. L. Ohringer et al., Acta Crystallogr., Sect. D: Biol. Crystallogr. 1996, D52(1), 224-225. PA1 .sup.5 J. R. Wetterau et al., J. Biol. Chem. 1990, 265, 9800-9807. PA1 .sup.6 J. R. Wetterau et al., Biochemistry 1991, 30, 4406-4412. PA1 .sup.7 C. C. Shoulders et al., J. Hum. Mol. Genet. 1993, 2, 2109-2116. PA1 .sup.8 R. Raag et al., J. Mol. Biol. 1988, 200, 553-569. PA1 .sup.9 P. A. Timmins et al., Science 1992, 257, 652-655. PA1 .sup.10 A. Atzel et al., Biochemistry 1993, 32, 10444-10450. PA1 .sup.11 A. Atzel et al., Biochemistry 1994, 33, 15382-15388. PA1 .sup.12 H. Jamil et al., J. Biol. Chem. 1995, 270, 6549-6554. PA1 .sup.13 H. Jamil et al., Proc. Natl. Acad. Sci. U.S.A. 1996, 93, 11991-11995. PA1 .sup.14 J. P. Kane et al., The Metabolic Basis of Inherited Disease, Scriver et al., Eds.; McGraw-Hill, N.Y., Ed. 7, 1995, pp. 1853-1885. PA1 .sup.15 M. F. Linton et al., J. Lipid Res. 1993, 34, 521-541. PA1 .sup.16 U.S. Pat. No. 5,712,279, issued Jan. 27, 1998 to Biller et al. PA1 .sup.17 U.S. Pat. No. 5,739,135, issued Apr. 14, 1998 to Biller et al. PA1 .sup.18 U.S. Pat. No. 5,760,246, issued Jun. 2, 1998 to Biller et al. PA1 .sup.19 U.S. Pat. No. 5,827,875, issued Oct. 27, 1998 to Dickson Jr. et al. PA1 .sup.20 U.S. Statutory Invention Registration No. H1729, published May 5, 1998 by Biller et al. PA1 .sup.21 WO 96/40640, published Dec. 19, 1996. PA1 .sup.22 WO 97/26240, published Jul. 24, 1997. PA1 .sup.23 WO 97/43255, published Nov. 20, 1997. PA1 .sup.24 WO 98/03069, published Jan. 29, 1998. PA1 .sup.25 WO 98/03174, published Jan. 29, 1998. PA1 .sup.26 WO 98/23593, published Jun. 4, 1998. PA1 .sup.27 WO 98/27979, published Jul. 2, 1998. PA1 .sup.28 WO 98/31225, published Jul. 23, 1998. PA1 .sup.29 WO 98/31366, published Jul. 23, 1998. PA1 .sup.30 WO 98/31367, published Jul. 23, 1998. PA1 .sup.31 EP 0 643 057 Al, published Mar. 15, 1995. PA1 .sup.32 M. Haghpassand et al., J. Lipid Res. 1996, 37, 1468-1480. PA1 .sup.33 F. Benoist et al., Eur. J. Biochem. 1996, 240, 713-720. PA1 .sup.34 J. R. Wetterau et al., Science 1998, 282, 751-754. PA1 wherein each X is independently a linker; p is an integer of from 2 to 10; and q is an integer of from 1 to 20; and each L is independently a ligand selected from the group consisting of: ##STR1## PA1 wherein PA1 each W is a divalent radical independently selected from the group consisting of: ##STR2## PA1 each R.sup.1 is independently selected from the group consisting of hydrogen, akyl, substituted alkyl, alkenyl, substituted alkenyl, cycloalkyl, substituted cycloalkyl, cycloalkenyl, substituted cycloalkenyl, aryl, heteroaryl and a covalent bond linking the ligand to a linker; PA1 each R.sup.2 is independently selected from the group consisting of hydrogen, alkyl, substituted alkyl, alkenyl, substituted alkenyl, cycloalkyl, substituted cycloalkyl, cycloalkenyl, substituted cycloalkenyl, aryl, heteroaryl and a covalent bond linking the ligand to a linker; PA1 each R.sup.3 is independently selected from the group consisting of hydrogen, alkyl and halo; PA1 each R.sup.4 is independently selected from the group consisting of hydrogen, alkyl, substituted alkyl, alkenyl, substituted alkenyl and a covalent bond linking the ligand to a linker; PA1 each R.sup.5 is independently selected from the group consisting of alkyl, substituted alkyl, alkenyl, substituted alkenyl, alkynyl, substituted alkynyl, cycloalkyl, substituted cycloalkyl, cycloalkenyl, substituted cycloalkenyl, alkoxy, substituted alkoxy, cycloalkoxy, substituted cycloalkoxy, aryl, aryloxy, heteroaryl, heteroaryloxy, amino, substituted amino and a covalent bond linking the ligand to a linker; or R.sup.4 and R.sup.5 may be joined, together with the &gt;NC(O)-- group to which they are attached, to form a heterocyclic ring; PA1 each R.sup.6 is independently selected from the group consisting of hydrogen, alkyl, substituted alkyl, alkenyl, substituted alkenyl, cycloalkyl, substituted cycloalkyl, cycloalkenyl, substituted cycloalkenyl, aryl, heteroaryl and a covalent bond linking the ligand to a linker; PA1 each R.sup.7 is independently selected from the group consisting of hydrogen, alkyl, substituted alkyl, alkenyl, substituted alkenyl, cycloalkyl, substituted cycloalkyl, cycloalkenyl, substituted cycloalkenyl, aryl, heteroaryl, heterocyclic, a covalent bond linking the ligand to a linker and --NR.sup.14 R.sup.15, where R.sup.14 is selected from the group consisting of hydrogen, alkyl, substituted alkyl, alkenyl, substituted alkenyl, cycloalkyl, substituted cycloalkyl, cycloalkenyl, substituted cycloalkenyl, aryl and heteroaryl; and R.sup.15 is a covalent bond linking the ligand to a linker; PA1 each R.sup.8 is independently selected from the group consisting of hydrogen, acyl, alkyl, substituted alkyl, alkenyl, substituted alkenyl, cycloalkyl, substituted cycloalkyl, cycloalkenyl, substituted cycloalkenyl, aryl, heteroaryl, heterocyclic, a covalent bond linking the ligand to a linker PA1 each R.sup.9 is independently selected from the group consisting of hydrogen, alkyl, substituted alkyl, alkenyl, substituted alkenyl, cycloalkyl, substituted cycloalkyl, cycloalkenyl, substituted cycloalkenyl, aryl, heteroaryl, heterocyclic, a covalent bond linking the ligand to a linker and --NR.sup.14 R.sup.15, where R.sup.14 is selected from the group consisting of hydrogen, alkyl, substituted alkyl, alkenyl, substituted alkenyl, cycloalkyl, substituted cycloalkyl, cycloalkenyl, substituted cycloalkenyl, aryl and heteroaryl; and R.sup.15 is a covalent bond linking the ligand to a linker; PA1 each R.sup.10, R.sup.11, R.sup.12 and R.sup.13 is independently selected from the group consisting of hydrogen, alkyl, substituted alkyl, alkenyl, substituted alkenyl, alkynyl, substituted alkynyl, cycloalkyl, substituted cycloalkyl, cycloalkenyl, substituted cycloalkenyl, alkoxy, substituted alkoxy, cycloalkoxy, substituted cycloalkoxy, aryl, aryloxy, halo, heteroaryl, heteroaryloxy, thioalkoxy, substituted thioalkoxy, thioaryloxy, thioheteroaryloxy, acyloxy, aminoacyl, aminocarbonyl, --S(O)R.sup.16 and --SO.sub.2 R.sup.16, where each R.sup.16 is independently selected from the group consisting of alkyl, substituted alkyl, alkenyl, substituted alkenyl, cycloalkyl, substituted cycloalkyl, aryl and heteroaryl; PA1 each ring A, together with the atoms to which it is attached, forms a carbocyclic or heterocyclic ring selected from the group consisting of aryl, cycloalkyl, substituted cycloalkyl, cycloalkenyl, substituted cycloalkenyl, heteroaryl and heterocyclic; PA1 each ring B, together with the atoms to which it is attached, forms a carbocyclic or heterocyclic ring selected from the group consisting of aryl, cycloalkyl, substituted cycloalkyl, cycloalkenyl, substituted cycloalkenyl, heteroaryl and heterocyclic; PA1 each ring C, together with the nitrogen atom to which it is attached, forms heterocyclic ring; PA1 each Q is independently selected from the group consisting of a covalent bond, --O--, --S--, --S(O)--, --SO.sub.2 --, alkylene, substituted alkylene, alkenylene, substituted alkenylene and --NR.sup.17 --, where R.sup.17 is selected from the group consisting of alkyl, substituted alkyl, alkenyl, substituted alkenyl, cycloalkyl, substituted cycloalkyl, cycloalkenyl, substituted cycloalkenyl, aryl and heteroaryl; PA1 each a is independently an integer of from 2 to 6; PA1 each b is independently an integer of from 0 to 6; PA1 each c is independently an integer of from 2 to 4; PA1 and pharmaceutically-acceptable salts or pro-drugs thereof; PA1 provided that when p is 2, q is 1 and a first ligand has formula IA or IB, where R.sup.1 or R.sup.2 is a covalent bond linking the first ligand to the linker, then a second ligand does not have formula ID or IE, where R.sup.8 or R.sup.9 are a covalent bond linking the second ligand to the linker. PA1 wherein PA1 each R.sup.18 and R.sup.19 are independently selected from the group consisting of hydrogen or halo; and PA1 Q' is a covalent bond, --O-- or --S--. PA1 wherein X' is a linker; and each L' is a ligand independently selected from the group consisting of: ##STR4## PA1 wherein PA1 each R.sup.22 and R.sup.21 is independently selected from the group consisting of hydrogen and halo; PA1 each R.sup.23 is independently selected from the group consisting of hydrogen and a covalent bond linking the ligand to the linker; PA1 each R.sup.24 is independently selected from the group consisting of hydrogen and a covalent bond linking the ligand to the linker; PA1 each R.sup.25 is independently selected from the group consisting of aryl, heteroaryl, heterocyclic, cycloalkyl, substituted cycloalkyl and a covalent bond linking the ligand to the linker; PA1 each R.sup.26 is independently selected from the group consisting of hydrogen, alkyl and a covalent bond linking the ligand to the linker; PA1 each R.sup.27 is independently selected from the group consisting of hydrogen, a covalent bond linking the ligand to a linker and --NR.sup.30 R.sup.31, where R.sup.30 is selected from the group consisting of hydrogen and alkyl; and R.sup.31 is a covalent bond linking the ligand to a linker; PA1 each R.sup.28 is a covalent bond linking the ligand to a linker; PA1 each R.sup.29 is independently selected from the group consisting of a covalent bond linking the ligand to a linker and --NR.sup.30 R.sup.31, where R.sup.30 is selected from the group consisting of hydrogen and alkyl; and R.sup.31 is a covalent bond linking the ligand to a linker; PA1 each Q" is independently selected from the group consisting of a covalent bond, --O-- and --S-- PA1 each a is independently an integer of from 2 to 6; PA1 each b is independently an integer of from 0 to 6; PA1 and pharmaceutically-acceptable salts or pro-drugs thereof; PA1 provided that in each ligand only one of R.sup.23, R.sup.24, R.sup.25, R.sup.26, R.sup.27, R.sup.28 and R.sup.29 is a covalent bond linking the ligand to the linker; PA1 and further provided that when a first ligand has formula IIA or IIB, where R.sup.23 is a covalent bond linking the first ligand to the linker, then a second ligand does not have formula IID or IIE, where R.sup.28 or R.sup.29 are a covalent bond linking the second ligand to the linker. PA1 wherein PA1 m is an integer of from 0 to 20; PA1 X.sup.a at each separate occurrence is selected from the group consisting of --O--, --S--, --NR--, --C(O)--, --C(O)O--, --C(O)NR--, --C(S), --C(S)O--, --C(S)NR-- or a covalent bond where R is as defined below; PA1 Z is at each separate occurrence is selected from the group consisting of alkylene, substituted alkylene, cycloalkylene, substituted cylcoalkylene, alkenylene, substituted alkenylene, alkynylene, substituted alkynylene, cycloalkenylene, substituted cycloalkenylene, arylene, heteroarylene, heterocyclene, or a covalent bond; PA1 Y.sup.a and Y.sup.b at each separate occurrence are selected from the group consisting of --C(O)NR'--, --NR'C(O)--, --NR'C(O)NR'--, --C(.dbd.NR')--NR'--, --NR'--C(.dbd.NR')--, --NR'--C(O)--O--, --N.dbd.C(X.sup.a)--NR'--, --P(O)(OR')--O--, --S(O).sub.n CR'R"--, --S(O).sub.n --NR'--, --S--S-- and a covalent bond; where n is 0, 1 or 2; and R, R' and R" at each separate occurrence are selected from the group consisting hydrogen, alkyl, substituted alkyl, cycloalkyl, substituted cycloalkyl, alkenyl, bstituted alkenyl, cycloalkenyl, substituted cycloalkenyl, alkynyl, substituted kynyl, aryl, heteroaryl and heterocyclic. PA1 (a) identifying a ligand or a mixture of ligands wherein each ligand contains at least one reactive functionality; PA1 (b) identifying a library of linkers wherein each linker in said library comprises at least two functional groups having complementary reactivity to at least one of the reactive functional groups of the ligand; PA1 (c) preparing a multimeric ligand compound library by combining at least two stoichiometric equivalents of the ligand or mixture of ligands identified in (a) with the library of linkers identified in (b) under conditions wherein the complementary functional groups react to form a covalent linkage between said linker and at least two of said ligands; and PA1 (d) assaying the multimeric ligand compounds produced in the library prepared in (c) above to identify multimeric ligand compounds possessing multibinding properties for microsomal triglyceride transferase protein. PA1 (a) identifying a library of ligands wherein each ligand contains at least one reactive functionality; PA1 (b) identifying a linker or mixture of linkers wherein each linker comprises at least two functional groups having complementary reactivity to at least one of the reactive functional groups of the ligand; PA1 (c) preparing a multimeric ligand compound library by combining at least two stoichiometric equivalents of the library of ligands identified in (a) with the linker or mixture of linkers identified in (b) under conditions wherein the complementary functional groups react to form a covalent linkage between said linker and at least two of said ligands; and PA1 (d) assaying the multimeric ligand compounds produced in the library prepared in (c) above to identify multimeric ligand compounds possessing multibinding properties for microsomal triglyceride transferase protein. PA1 (a) identifying a ligand or a mixture of ligands wherein each ligand contains at least one reactive functionality; PA1 (b) identifying a library of linkers wherein each linker in said library comprises at least two functional groups having complementary reactivity to at least one of the reactive functional groups of the ligand; and PA1 (c) preparing a multimeric ligand compound library by combining at least two stoichiometric equivalents of the ligand or mixture of ligands identified in (a) with the library of linkers identified in (b) under conditions wherein the complementary functional groups react to form a covalent linkage between said linker and at least two of said ligands. PA1 (a) identifying a library of ligands wherein each ligand contains at least one reactive functionality; PA1 (b) identifying a linker or mixture of linkers wherein each linker comprises at least two functional groups having complementary reactivity to at least one of the reactive functional groups of the ligand; and PA1 (c) preparing a multimeric ligand compound library by combining at least two stoichiometric equivalents of the library of ligands identified in (a) with the linker or mixture of linkers identified in (b) under conditions wherein the complementary functional groups react to form a covalent linkage between said linker and at least two of said ligands. PA1 (a) preparing a first collection or iteration of multimeric compounds which is prepared by contacting at least two stoichiometric equivalents of the ligand or mixture of ligands which target a receptor with a linker or mixture of linkers wherein said ligand or mixture of ligands comprises at least one reactive functionality and said linker or mixture of linkers comprises at least two functional groups having complementary reactivity to at least one of the reactive functional groups of the ligand wherein said contacting is conducted under conditions wherein the complementary functional groups react to form a covalent linkage between said linker and at least two of said ligands; PA1 (b) assaying said first collection or iteration of multimeric compounds to assess which if any of said multimeric compounds possess multibinding properties for microsomal triglyceride transferase protein; PA1 (c) repeating the process of (a) and (b) above until at least one multimeric compound is found to possess multibinding properties for microsomal triglyceride transferase protein; PA1 (d) evaluating what molecular constraints imparted or are consistent with imparting multibinding properties to the multimeric compound or compounds found in the first iteration recited in (a)-(c) above; PA1 (e) creating a second collection or iteration of multimeric compounds which elaborates upon the particular molecular constraints imparting multibinding properties to the multimeric compound or compounds found in said first iteration; PA1 (f) evaluating what molecular constraints imparted or are consistent with imparting enhanced multibinding properties to the multimeric compound or compounds found in the second collection or iteration recited in (e) above; PA1 (g) optionally repeating steps (e) and (f) to further elaborate upon said molecular constraints.
All of the above publications are herein incorporated by reference in their entirety to the same extent as if each individual publication was specifically and individually indicated to be incorporated by reference in its entirety.
2. State of the Art
Microsomal triglyceride transferase protein (MTP) is a lipid transfer protein which mediates the transport of lipids, such as triglycerides, cholesterol esters, and phosphatidylcholine, between membranes..sup.1,2 Accordingly, MTP is believed to play a role in the assembly of lipoproteins and related biomolecules. In this regard, MTP has been implicated as a probable agent in the assembly of apolipoprotein B (Apo B)-containing lipoproteins which are known to contribute to the formation of atherosclerotic lesions. Thus, effective inhibitors of MTP would be useful in preventing the onset and progression of atherosclerosis, including myocardial infarction, stroke, peripheral vascular disease and the like, which accounts for one-half of deaths in the United States..sup.3
MTP was originally isolated from the microsomal fraction of bovine liver and has subsequently been found within the lumen of microsomes isolated from both the liver and intestine..sup.1 Since its initial isolation, MTP has been extensively characterized..sup.4,5,6 MTP is a soluble, heterodimeric protein composed of 58 and 97 kDa subunits, both of which are required for activity. The protein is localized within the lumen of the endoplasmic reticulum. The 58 kDa subunit is identical to protein disulfide isomerase (PDI), though the complex exhibits no PDI activity and isolated PDI does not exhibit MTP activity. The noncovalent MTP heterodimer does not display significant dissociation/reassociation and is either asymmetric and/or highly hydrated. The unique 97 kDa subunit bears homology to other lipid-transporting proteins, including the lipovitillin-phosvitin complex (LPC) and, to a lesser extent, plasma cholesteryl ester transfer protein (CETP)..sup.7 Structural characterization of LPC reveals that it comprises a large cavity that complexes multiple copies of phospholipid..sup.8,9
Kinetic analysis of the MTP-mediated lipid transport processes have revealed ping pong bi bi kinetics which is consistent with a mechanism of action in which MTP binds and shuttles lipid molecules between membranes..sup.10 This suggests that stable MTP-lipid complexes are formed during the transfer process, which is further supported by the observation that incubation of MTP with donor vesicles containing a variety of radio-labeled lipids followed by re-isolation affords MTP containing up to three molecules of lipid..sup.11,12 The ability of lipid molecules to occupy distinct binding sites on MTP is suggested by the observation of biphasic kinetics for transfer of phosphatidyl choline, which binds with a 2:1 stoichiometry to the enzyme..sup.12 Moreover, an MTP inhibitor has been hown to fully ablate the MTP-mediated transfer of triglycerides and cholesterol sters but not that of phosphatidyl choline..sup.13
The ability of MTP inhibitors to prevent the onset and progression of therosclerosis and related disorders is supported by the observation that utations in MTP are the only known bases for abetalipoproteinemia, an autosomal recessive disorder characterized by the virtual absence of apoB-containing plasma lipoproteins..sup.1,2,14 Abetalipoproteinemia sub atherosclerosis, but they suffer from a variety of side effects as a result of the extreme nature of their condition. This suggests that non-complete inhibition of MTP would be requisite in an agent designed for human therapy. In this regard, hypobetalipoproteinemia is a relevant model for MTP inhibition. This condition is displayed by individuals who are heterozygous for mutations in apolipoproteinB..sup.15 These subjects have levels of apoB-containing lipoproteins half that of normal subjects and, as a result, they enjoy extended lifespans.
Inhibitors of MTP have been described in the patent and technical literature. See, by way of example, U.S. Pat. No. 5,712,279;.sup.16 U.S. Pat. No. 5,739,135;.sup.17 U.S. Pat. No. 5,760,246;.sup.18 U.S. Pat. No. 5,827,875;.sup.19 U.S. Statutory Invention Registration No. H1729;.sup.20 WO 96/40640;.sup.21 WO 97/26240;.sup.22 WO 97/43255;.sup.23 WO 98/03069;.sup.24 WO 98/03174;.sup.25 WO 98/23593;.sup.26 WO 98/27979;.sup.27 WO 98/31225;.sup.28 WO 98/31366;.sup.29 WO 98/31367;.sup.3 EP 0 643 057 A1;.sup.31 M. Haghpassand et al.;.sup.32 F. Benoist et al.;.sup.33 and J. R. Wetterau et al..sup.34 Notwithstanding such inhibitors, a need exists for effective MTP inhibitors having improved biological and/or therapeutic effects.
It has now been discovered that MTP inhibitors having surprising and unexpected properties can be prepared by linking from 2 to 10 ligands capable of binding to MTP to one or more linkers. The chemical structure of one known inhibitor of MTP, i.e. BMS-201038, is illustrated in FIG. 1A..sup.16,34 Without being limited to theory, a potential complex of this compound with MTP is illustrated in FIG. 1B. Based on the distinct multiple binding sites believed to be present in MTP, various multibinding compounds are illustrated in FIG. 1B. Such multibinding compounds provide greater biological and/or therapeutic effects than the aggregate of the unlinked ligands due to their multibinding properties.